U.S. patent application number 13/720380 was filed with the patent office on 2013-06-20 for sewing machine.
This patent application is currently assigned to TOKAI KOGYO MISHIN KABUSHIKI KAISHA. The applicant listed for this patent is TOKAI KOGYO MISHIN KABUSHIKI KAISHA. Invention is credited to Mitsunori Matsumoto.
Application Number | 20130152838 13/720380 |
Document ID | / |
Family ID | 48522166 |
Filed Date | 2013-06-20 |
United States Patent
Application |
20130152838 |
Kind Code |
A1 |
Matsumoto; Mitsunori |
June 20, 2013 |
Sewing Machine
Abstract
A pulling device is configured to grip, after cutting of a
sewing material, a suitable portion of the sewing material by means
of a grip member, where a leading end portion of the sewing
material having been pulled out from a guide device, and pull back
the sewing material by movement of the grip member having the
sewing material gripped thereby. Thus, the leading end portion of
the sewing material, pulled out and extending from the guide device
more than necessary, can be minimized to a length necessary for the
sewing material to be reliably sewn onto a sewing object at an
initial stage of a next sewing operation. In this way, it is
possible to minimize a length of a portion of the sewing material
that was heretofore wasted without being sewn onto the sewing
object.
Inventors: |
Matsumoto; Mitsunori;
(Tajimi-shi, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TOKAI KOGYO MISHIN KABUSHIKI KAISHA; |
Kasugai-shi |
|
JP |
|
|
Assignee: |
TOKAI KOGYO MISHIN KABUSHIKI
KAISHA
Kasugai-shi, Aichi-jen
JP
|
Family ID: |
48522166 |
Appl. No.: |
13/720380 |
Filed: |
December 19, 2012 |
Current U.S.
Class: |
112/285 |
Current CPC
Class: |
D05C 7/08 20130101; D05B
65/02 20130101; D05C 11/20 20130101; D05B 37/04 20130101 |
Class at
Publication: |
112/285 |
International
Class: |
D05C 11/20 20060101
D05C011/20; D05B 65/02 20060101 D05B065/02 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 20, 2011 |
JP |
2011278225 |
Claims
1. A sewing machine comprising: a sewing needle mounted to a lower
end portion of a vertically-driven needle bar; a guide device for
guiding an elongated sewing material to a needle drop position of
the sewing needle in response to a sewing operation for sewing the
sewing material onto a sewing object; a cutting device for cutting
the sewing material after moving the sewing object, having the
sewing material sewn thereon through lock stitching, so that a
sewing end point of the sewing material is moved from the needle
drop position to be located at a predetermined position away from
the needle drop position and then pulling the sewing material out
from the guide device; and a pulling device for pulling back the
sewing material, whose leading end portion has been pulled out from
said guide device, after the cutting by said cutting device, and
thereby reducing a length of the leading end portion of the sewing
material extending out from said guide device.
2. The sewing machine as claimed in claim 1, wherein said pulling
device includes a grip device for gripping the sewing material, and
a drive device for moving the grip device, and wherein said pulling
device pulls back the sewing material, whose leading end portion
has been pulled out from said guide device at a time of the cutting
by said cutting device, by said drive device moving said grip
device with the sewing material gripped thereby.
3. The sewing machine as claimed in claim 2, wherein said pulling
device further includes a release device for releasing the sewing
material from gripping by said grip device, timing for releasing
the sewing material being changeable, and wherein a length by which
the sewing material, whose leading end portion has been pulled out
from said guide device, is to be pulled back is adjustable in
accordance with a change in the timing for releasing the sewing
material.
4. The sewing machine as claimed in claim 2, wherein said grip
device includes a fixed portion fixedly mounted to a body of said
grip device, and a movable portion movably mounted to the body of
said grip device, and wherein, in response to movement in one
direction, by said drive device, of said grip device, the movable
portion is moved so that the sewing material is gripped between the
movable portion and the fixed portion, and, in response to movement
in an opposite direction from the one direction, by said drive
device, of said grip device, the sewing material gripped between
the movable portion and the fixed portion is pulled back in an
opposite direction from the direction the sewing material was
pulled out from said guide device after the cutting by said cutting
device.
Description
BACKGROUND
[0001] The present invention relates to sewing machines of a type
provided with a cutting device that, in response to completion of a
sewing operation where a tape or cord or other elongated sewing
material having been guided by a guide device to a needle drop
position is sewn by lock stitching onto a sewing workpiece or
sewing object (e.g., fabric) through loop stitching, pulls out the
sewing material from the guide device and cuts the pulled-out
elongated sewing material.
[0002] Heretofore, there have been known sewing machines of a type
which includes: a vertically-driven needle bar; a sewing needle
fixed to the lower end of the needle bar; a rotary member mounted
concentrically with the needle bar and freely rotatable about the
axis of the needle bar; and a guide device (guide) fixed to the
rotary member for guiding an elongated sewing material (e.g.,
string-shaped embroidering material, such as a tape or cord) to a
needle drop position of the sewing needle. The sewing machines of
this type operate to sew the sewing material to the sewing
workpiece or sewing object (e.g., fabric) by lock stitching while
controlling the rotation of the rotary member in accordance with a
moving direction of the sewing object based on embroidery data and
appropriately adjusting the orientation of the guide to optimize
the direction in which the sewing material is guided to the needle
drop position of the sewing needle. Some of the
conventionally-known sewing machines of the aforementioned type are
provided with a cutting device for automatically cutting the sewing
material, having been pulled out to the needle drop position, with
a view to reducing a load imposed on a human operator when an
operation for sewing the sewing material to the sewing object has
been completed. An example of such sewing machines is known from
Japanese Patent Application Laid-open Publication No. 2007-68829
(hereinafter referred to as "relevant patent literature").
[0003] In the sewing machine disclosed in the aforementioned
relevant patent literature, the cutting device for cutting the
sewing material is located apart from the needle drop position. Now
briefly explaining the cutting device disclosed in the relevant
patent literature, the cutting device includes a cutting member
movable between an evacuation position where the cutting device
does not disturb the sewing operation and a cutting position where
it can cut the sewing material. When the sewing material is to be
cut, the sewing object is moved to move a sewing end point of the
sewing material from the needle drop position to near the cutting
device, and then the cutting member is moved from the evacuation
position to the cutting position.
[0004] The cutting member disclosed in the relevant patent
literature includes a catch section that catches the sewing
material as the cutter member moves from the evacuation position to
the cutting position, a cutting blade that operates in response to
further movement of the cutter member to the cutting position after
the catch section has caught the sewing material, and a fixed blade
that cuts the sewing material in conjunction with the cutting
blade. Namely, as the cutting member moves from the evacuation
position to the cutting position, the sewing material is caught by
the catch member, and the cutting blade is moved, in interlocked
relation to the further movement of the cutting member with the
sewing material caught by the catch member, so that the sewing
material is cut through cooperation between the cutting blade and
the fixed blade.
[0005] In the sewing machines of the aforementioned type, a leading
end portion of the sewing material, pulled to extend out from the
guide in preparation for a next sewing operation, has to have a
given length such that the sewing material can be reliably sewn to
the sewing object at an initial stage of the next sewing operation.
Thus, the sewing machines provided with the cutting device as
disclosed in the relevant patent literature is constructed to
secure a sufficient length of the leading end portion of the sewing
material that should extend out from the guide after completion of
the cutting operation, by moving the sewing object by some extra
distance from the guide at the time of the cutting of the sewing
material. By securing such a sufficient length of the leading end
portion of the sewing material which should extend out from the
guide in preparation for a next sewing operation, it is possible to
reliably sew the sewing material onto the sewing object at the
initial stage of a next sewing operation.
[0006] However, in the cutting device disclosed in the
aforementioned relevant patent literature, the leading end portion
of the sewing material tends to extend out from the guide after
completion of the cutting operation more than the length necessary
for the sewing material to be reliably sewn at the initial stage of
a next sewing operation, because a mounted position of the cutting
device depends on positional relationship among various component
parts fixed to a machine head, the member rotation-controlled in
accordance with a moving direction of the sewing object, etc.
Further, because of the fact that the sewing material is sewn to
the sewing object starting at a sewing start point located near the
guide, most of the leading end portion of the sewing material,
extending out from the guide, would not be sewn onto the sewing
object at the initial stage of a next sewing operation. Because
such a portion of the sewing material that could not be sewn onto
the sewing object is discarded after being cut manually by the
human operator, that portion of the sewing material would result in
a considerable waste.
[0007] In order to avoid such a waste of the sewing material, it is
preferable to minimize the length of the leading end portion of the
sewing material extending out from the guide while at the same time
securing the length necessary for the sewing material to be
reliably sewn onto the sewing object at the initial stage of a next
sewing operation. Further, because the necessary length for the
sewing material to be reliably sewn onto the sewing object differs
depending on the types of the sewing material and the sewing
object, it is preferable to permit desired adjustment of the length
of the leading end portion of the sewing material, extending out
from the guide before that start of a sewing operation, depending
on the types of the sewing material and the sewing object. However,
no sewing machine capable of realizing such a minimized length of
the leading end portion and desired adjustment of the length of the
leading end portion has not been proposed yet.
SUMMARY OF THE INVENTION
[0008] In view of the foregoing, it is an object of the present
invention to provide an improved sewing machine which includes a
cutting device that, in response to completion of sewing of a
sewing material onto a sewing object, pulls out and cuts a leading
end portion of the sewing material, and which can minimize the
length of the leading end portion of the sewing material extending
out from a guide while at the same time securing a length necessary
for the sewing material to be reliably sewn onto the sewing object
at the initial stage of a next sewing operation.
[0009] It is another object of the present invention to provide an
improved sewing machine which permits desired adjustment of a
length of a leading end portion of the sewing material, which
extends out from a guide before the start of a sewing operation,
depending on types of the sewing material and sewing object.
[0010] In order to accomplish the above-mentioned objects, the
present invention provides an improved sewing machine, which
comprises: a sewing needle mounted to a lower end portion of a
vertically-driven needle bar; a guide device for guiding an
elongated sewing material to a needle drop position of the sewing
needle in response to a sewing operation for sewing the sewing
material onto a sewing object; a cutting device for cutting the
sewing material after moving the sewing object, having the sewing
material sewn thereon through lock stitching, so that a sewing end
point of the sewing material is moved from the needle drop position
to be located at a predetermined position away from the needle drop
position and then pulling the sewing material out from the guide
device; and a pulling device for pulling back the sewing material,
whose leading end portion has been pulled out from the guide
device, after the cutting by the cutting device, and thereby
reducing a length of a leading end portion of the sewing material
extending out from the guide device.
[0011] In a preferred embodiment of the sewing machine, the pulling
device includes a grip device for gripping the sewing material, and
a drive device for moving the grip device, and the pulling device
pulls back the sewing material, whose leading end portion has been
pulled out from the guide device, after the cutting by the cutting
device, by the drive device moving the grip device with the sewing
material gripped thereby.
[0012] According to the present invention, the pulling device pulls
back, after the cutting of the sewing material, the sewing material
having its leading end portion pulled to extend out from the guide
device. Thus, a leading end portion of the sewing material,
extending out from the guide device more than necessary, can be
minimized to a length necessary for the sewing material to be
reliably sewn onto the sewing object at an initial stage of a next
sewing operation. In this way, it is possible to minimize a length
of a portion of the sewing material that was heretofore wasted
without being sewn onto the sewing object.
[0013] Further, with the present invention, it is possible to
change as desired a length by which the sewing material, pulled out
from the guide device, is to be pulled back after the cutting, by
the drive device moving the grip device, having the cut sewing
material gripped thereby, to pull back the pulled-out sewing
material and by changing the timing at which the sewing material
should be released, via the release device, from the gripping by
the grip device. In this way, a human operator can readily adjust
the length of the leading end portion of the sewing material, which
should extend out from the guide in preparation for a next sewing
operation, to a desired length depending on the types of the sewing
material and sewing object.
[0014] According to the present invention, the sewing material,
pulled out from the guide device, is gripped and pulled back after
the cutting, by the cutting device, of the sewing material. Thus,
the leading end portion of the sewing material, extending out from
the guide device more than necessary, can be minimized to a length
necessary for the sewing material to be reliably sewn onto a sewing
object at an initial stage of a next sewing operation. In this way,
it is possible to minimize a length of a portion of the sewing
material that would be wasted without being sewn onto the sewing
object.
[0015] Further, because a length by which the sewing material,
whose leading end portion has been pulled out from the guide
device, should be pulled back can be adjusted in accordance with a
change in the timing for releasing, via the release device, the
sewing material from the gripping by the grip device, the human
operator can readily adjust the length of the leading end portion
of the sewing material, which should extend out from the guide
device in preparation for a next sewing operation, to a desired
length depending on the types of the sewing material and sewing
object.
[0016] The following will describe embodiments of the present
invention, but it should be appreciated that the present invention
is not limited to the described embodiments and various
modifications of the invention are possible without departing from
the basic principles. The scope of the present invention is
therefore to be determined solely by the appended claims.
BRIEF DESCRIPTION OF DRAWINGS
[0017] For better understanding of the object and other features of
the present invention, its preferred embodiments will be described
hereinbelow in greater detail with reference to the accompanying
drawings, in which:
[0018] FIG. 1 is a plan view showing an embodiment of a multi-head
embroidery sewing machine of the present invention;
[0019] FIG. 2 is a front view showing an example of a supply
stand;
[0020] FIG. 3 is a plan view showing a stored state of an original
fabric on the supply stand;
[0021] FIG. 4 is a front view showing an example of a machine head
in the embroidery sewing machine;
[0022] FIG. 5 is a left side view showing the example of the
machine head;
[0023] FIG. 6 is a schematic front view showing an example of a
pulling device in the embroidery sewing machine;
[0024] FIG. 7 is a schematic plan view explanatory of pulling of a
sewing material and particularly showing a sliding block in a
raised position; and
[0025] FIG. 8 is a schematic plan view explanatory of the pulling
of the sewing material and particularly showing the sliding block
in a lowered position.
DETAILED DESCRIPTION
[0026] The following describe in detail a preferred embodiment of
the present invention with reference to the accompanying
drawings.
[0027] FIG. 1 is a plan view showing a preferred embodiment of an
embroidery sewing machine of the present invention, FIG. 2 is a
front view of an example of a supply stand S, and FIG. 3 is a plan
view showing a stored state of an original fabric N on the supply
stand S. Hereinbelow, a preferred embodiment of a multi-head
embroidery sewing machine having a plurality of machine heads will
be described with primary reference to FIGS. 1 to 3. Note that, in
FIG. 1, the multi-head embroidery sewing machine is shown with an
upper section of a machine frame 1 recessed and thus illustration
of the later-described machine heads (see FIGS. 4 and 5) is
omitted.
[0028] A plurality of machine heads are provided on the front
surface (corresponding to the lower end side in FIG. 1 and the
surface closer to a reader of FIG. 2) at predetermined intervals
along a left-right direction of the multi-head embroidery sewing
machine. Each of the machine heads is capable of sewing an
elongated sewing material, such as a tape or cord, to a sewing
workpiece or sewing object, such as a fabric, leather or other
material. A table 2 of a flat plate shape is provided underneath
these machine heads. Needle plates 3 are provided on the table 2 at
positions corresponding to the positions of the machine heads.
Further, a fabric frame 4 for holding a sewing object (also
referred to also as "original fabric") N is placed on the table 2,
and the fabric frame 4 is drivable in front-rear and left-right
directions along the table 2 by means of an X drive mechanism 5 and
a Y drive mechanism 6 provided underneath the table 2.
[0029] In the instant embodiment of the multi-head embroidery
sewing machine, an elongated original fabric N is supplied from a
supply source S (i.e., later-described supply stand S) to the
fabric frame 4 so that a portion of the original fabric N is
fixedly held on the fabric frame 4. Once sewing of the sewing
material onto the portion of the original fabric N fixedly held on
the fabric frame 4 is completed, the original fabric N is moved
relative to the fabric frame 4 so that another portion of the
original fabric N is fixedly held on the fabric frame 4, and then,
the sewing is re-started to sew the sewing material to the other
portion of the original fabric N.
[0030] In order to fixedly hold one or more original fabrics N on
each of left and right machine sections demarcated along a
centerline extending across the width of the embroidery sewing
machine, two pairs of front and rear horizontal clamp members 7a
and 7b are disposed on left and right side sections on the fabric
frame 4 in opposed relation to each other. On each of the clamp
members 7a and 7b, pairs of guide members 12 are provided in
corresponding relation to individual original fabrics N for guiding
left and right portions of the corresponding fabrics N. Each of the
original fabrics N is passed between the corresponding pairs of
guide members 12. Each pair of the guide members 12 opposed to each
other in the left-right direction of FIG. 1 are adjustable in
position in accordance with the width of the corresponding original
fabric N. With one or more original fabrics N sandwiched between
the pair of opposed horizontal clamp members 7a and 7b, the one or
more original fabrics N supplied from the supply source S can be
simultaneously fixed at respective predetermined positions of the
fabric frame 4.
[0031] With the aforementioned construction where no machine head
and needle plate 3 are provided in a middle region of the fabric
frame 4, the sewing material cannot be sewn to the original fabric
M on the central region of the fabric frame 4. Instead, in the
middle region of the fabric frame 4, a reinforcing member 8 spans
between and is fixed to the front and rear sides of the fabric
frame 4, with a view to preventing deformation of the fabric frame
4 to thereby prevent differences in sewn position, on the
individual original fabrics N, of the sewing materials that might
be caused due to the deformation of the fabric frame 4.
[0032] Two supply stands S for supporting original fabrics N are
provided behind the back or rear surface of the multi-head
embroidery sewing machine in corresponding relation to the pairs of
horizontal clamp members 7a and 7b that are provided on front and
rear longitudinal edge portions of the fabric frame 4 and extending
in the left-right direction of the fabric frame 4. These supply
stands S are capable of supporting original fabrics N corresponding
in number to the machine heads. As illustratively shown in FIG. 2,
each of the supply stands S is constructed in a two-deck structure
comprising upper and lower decks such that the original fabrics N
to be used by the individual machine heads can be supported
dividedly on the upper and lower decks in a vertically-staggered
row.
[0033] In the supply stands S, as shown in FIGS. 2 and 3, one
original fabric N is set in a rolled state on each drum 9. Pairs of
support rods 10 parallel spaced from each other by a predetermined
distance in the front-rear direction are provided; the number of
the pairs of support rods 10 corresponds to the number of the
machine heads. Per each of the pairs of support rods 10, four
support rollers 11 are supported on opposite end portions of the
front and rear support rods 10 in such a manner that the support
rollers 11 are immovable in an axial direction thereof; the drum 9
is rotatably supported by the four support rollers 11. The original
fabric N is supplied from each of the drums 9, supported on the
supply stands S, to the fabric frame 4.
[0034] The following describe the machine head H having a function
for sewing an elongated sewing material, such as a tape or cord, to
an original fabric N fixedly held on the fabric frame 4. FIG. 4 is
a front view showing an example of the machine head, and FIG. 5 is
a left side view showing the example of the machine head.
[0035] The machine head H shown in FIGS. 4 and 5 has a sewing
needle 14 mounted to a lower end portion of a needle bar disposed
to extend in an up-down direction (vertical direction) of the
sewing machine and reciprocatively driven, together with the needle
bar in the up-down direction, by rotation of a main machine shaft
13. Lock stitching is performed in the well-known manner through
the up-and-down (vertical) movement of the sewing needle 14 and
rotation of a not-shown rotary hook disposed underneath a needle
plate 3. In coaxial relation to the needle bar are provided a
rotary member 15 freely rotatable about the axis of the needle bar,
and a presser foot 16 not only rotatable together with the rotary
member 15 but also vertically movable in response to the vertical
movement of the sewing needle 14.
[0036] A guide lever 17 is mounted to the rotary member 15 and
driven to reciprocatively pivot at predetermined timing relative to
the vertical up-down movement of the needle bar 14, and a guide 18
is mounted to the distal end of the guide lever 17 for directing or
guiding a sewing material A to a needle drop position (sewing
position) of the sewing needle 14. The sewing machine sequentially
sews the sewing material A, guided to the needle drop position of
the sewing needle 14, onto the fabric N through zigzag sewing by
reciprocatively pivoting the guide lever 17 leftward and rightward
of the needle drop position per vertical reciprocating movement of
the sewing needle 14 while controlling the rotation of the rotary
member 15, in accordance with a moving direction of the fabric
frame 4 based on embroidery data, in such a manner as to optimize a
direction in which the sewing material A is to be guided.
[0037] A bobbin 19 having a cord-shaped sewing material A wound
thereon is rotatably provided above the machine head H. More
specifically, the bobbin 19 is rotatably supported on a bobbin
shaft 21 that is in turn supported at its opposite ends on a pair
of left and right support members 20 fixed to the machine frame 1.
A support plate 22 extending downward is fixed to one of the pair
of support members 20 (i.e., left support member 20 in FIG. 4). A
driving pulley 23 is disposed at a position of the support plate 22
closer to the proximal end of the support plate 22, and this
driving pulley 23 is fixedly connected to a motor shaft of a drive
motor 24 fixed to the left support member 22.
[0038] A driven pulley 25 is rotatably disposed at a position,
adjacent to the driving pulley 23, of the support plate 22 closer
to the distal end of the support plate 22, and a round belt 26 is
wound at its opposite end portions on the driven pulley 25 and the
driving pulley 23. The driven pulley 25 is fixed to one end portion
of a shaft 27 rotatably supported on a distal end portion of the
support plate 22, and a rotary pulley 28 having a non-slip member
wound thereon is fixed to another end portion of the shaft 27
opposite from the one end portion. The rotary pulley 28 is provided
in such a manner that its outer peripheral surface abuts against
the left lower end of a left flange of the bobbin 19. Thus, the
bobbin 19 rotates as the rotary pulley 28 rotates by being driven
by the drive motor 24 via the driving pulley 23 and the driven
pulley 25.
[0039] Further, a guide member 29 for guiding the sewing material A
paid out from the bobbin 19 is provided underneath the bobbin 19.
The guide member 29 is fixed to a pair of guide bases 30 that are
disposed on the two support members 20 and extending in the
vertical direction. Further, two guide rods 31 and 32 are provided
on an upper end portion and a substantially middle portion of the
guide member 29 and extend in a left-right direction of FIG. 4 with
a gap between the guide rods 31 and 32 and the rear surface of the
guide member 29. The sewing material A paid out from the bobbin 19
is guided through the gap between the guide rods 31 and 32 and the
rear surface of the guide member 29 toward a lower portion of the
sewing machine.
[0040] A rod 33 extending in the left-right direction of FIG. 4 is
provided underneath the guide member 29, and the rod 33 is fixed at
its opposite ends to lower end portions of a pair of left and right
pivot arms 34 and 35. The pivot arms 34 and 35 are pivotably
supported on the left and right guide bases 30, respectively. A
detector for detecting pivoting movement of the left pivot arm 34
is provided on the left guide base 20, and a timer 36 for
controlling a driving operation of the drive motor 24 is provided
on the left support member 20. As the pivot arm 34 is pivoted in
response to sewing of the sewing material A onto the original
fabric N, the drive motor 24 is driven for a predetermined time set
by the timer 36. Namely, the pivot arm 34 has a switch function for
starting the driving operation of the drive motor 24.
[0041] A mounting plate 37 of a substantially U shape is fixed to
the front surface of the guide member 29, and a guide collar 38 is
fixed to a middle region of a lower end portion of the mounting
plate 37. Further, as shown in FIG. 5, a first holder 40 is fixed
to the front surface of the machine head H via a first bracket 39
extending toward the front of the sewing machine. A flexible tube
41 for passage therethrough of the sewing material A is fixed at
one end to the first holder 40 and fixed at the other end to a
second holder 43 supported on a holder arm 42 extending from the
rotary member 15 as shown in FIG. 4. With such arrangements, the
sewing material A directed to the guide member 29 is abutted
against the back side of the rod 30, then passed through the guide
collar 38, tube 41 and guide 18 of the guide lever 17, and then
directed to the needle drop position of the sewing needle 14.
[0042] Further, a cutting device C for cutting the sewing material
A is disposed rightwardly and downwardly of the machine head H
provided on the front surface of the machine frame 1, as shown in
FIG. 4. The cutting device C may be any one of the
conventionally-known cutting devices including the one disclosed in
the aforementioned relevant patent literature, and thus, a
description about a construction of the cutting device C is omitted
here.
[0043] In the instant embodiment of the sewing machine of the
invention, a pulling device (pulling member) 44 is disposed in
front of the machine head H, and this pulling device (pulling
member) 44 is capable of adjusting a length of the sewing material
A to be directed through the guide (guide device) 18 to the needle
drop position of the sewing needle 14 by pulling the sewing
material A after the cutting operation, by the cutting device C, of
the sewing material A. A construction of the pulling device 44 will
be described below with reference to FIGS. 6 to 8. FIG. 6 is a
schematic front view showing an example of the pulling device 44,
and FIG. 7 is a schematic plan view explanatory of pulling of the
sewing material A and particularly showing a sliding block 50 in a
raised position. FIG. 8 is also a schematic plan view explanatory
of the pulling of the sewing material A and particularly showing
the sliding block 50 in a lowered position. Note that the lower end
side in FIGS. 7 and 8 corresponds to the front surface side of the
sewing machine.
[0044] As shown in FIG. 6, the pulling device 44 has a base 47 of a
generally C shape as viewed from the front of the sewing machine,
and this base 47 is fixed to the front surface of the machine head
H via the first bracket 39, second bracket 45 and third bracket 46.
The base 47 has two vertical guide rods 48 fixed thereto at a
predetermined distance therebetween. Further, an air cylinder
(drive device) 49 is provided on and extends vertically upward from
an upper end portion of the base 47. The sliding block (grip
device) 50, which is capable of being slidingly guided along the
two guide rods 48 and includes a movable piece 53 and a fixed piece
61, is fixed to the distal end of a rod of the air cylinder 49.
Namely, in response to driving operation of the air cylinder 49,
the sliding block 50 ascends and descends along the guide rods 48
between the raised position indicated by a solid line in FIG. 6 and
the lowered position indicated by a phantom line (two-dot-chain
line) in FIG. 6.
[0045] As shown in plan views of FIGS. 7 and 8, a support member 51
is fixed to the back surface of the sliding block 50, and a sliding
rod 52 is provided in the support member 51 in such a manner that
it is axially slidable in the longitudinal direction (left-right
direction in FIGS. 7 and 8) of the sliding block 50. The movable
piece (movable portion) 53 is fixed to a right end portion of the
sliding rod 52, and a compression spring 54 is provided on the
sliding rod 52 between the movable piece (movable portion) 53 and
the support member 51 for normally urging the sliding rod 52 in the
rightward direction in the figures. Further, a ball plunger 55 is
provided in the sliding block 50 with a ball provided at the distal
end thereof and projecting beyond the back surface of the sliding
block 50. The movable piece 53 has a recessed portion formed in the
front surface thereof for engagement with the ball of the ball
plunger 55 projecting beyond the back surface of the sliding block
50. When the sliding rod 52 has slid until the movable piece 53
reaches a position shown in FIG. 7, the ball of the ball plunger 55
engages with the recessed portion in the front surface of the
movable piece 53, so that the movable piece 53 is retained in the
position shown in FIG. 7 against the biasing force of the
compression spring 54.
[0046] Further, a roller 56 is fixed to a left end portion of the
sliding rod 52, and two (inner and outer) elongated holes 47a and
47b of different lengths are formed in different positions (inner
and outer positions) of the base 47 as shown in FIG. 6. In the
inner elongated hole 47a of the greater length is provided an upper
cam (release device) 57 having a slanting surface 57a that abuts
against the roller 56 to move the sliding rod 52 leftwardly as the
sliding block 50 ascends from the lowered position. Further, in the
outer elongated hole 47b of the smaller length is provided a lower
can 58 having a slanting surface 58a that abuts against the roller
56 to move the sliding rod 52 rightwardly as the sliding rod 50
descends from the raised position.
[0047] More specifically, the upper and lower cams 57 and 58 have
their projections (not shown) slidably engaging with the
corresponding elongated holes 47a and 47b, and these cams 57 and 58
are fixed at their respective desired positions by means of fixing
screws 59 and 60 after having been positioned by the user or human
operator at the desired positions along the corresponding elongated
holes 47a and 47b. Note that the upper and lower cams 57 and 58 are
prevented from rotation by the above-mentioned projections engaging
with the elongated holes 47a and 47b.
[0048] Furthermore, the fixed piece (fixed portion) 61 as well as
the support member 51 is fixed to the back surface of the sliding
block 50. As the sliding rod 52 moves in the rightward direction,
the fixed piece 61 sandwiches or grips the sewing material A in
conjunction with the movable piece 53 provided on the right end
portion of the sliding rod 52. The fixed piece 61 is disposed on a
back surface position of the sliding block 50 such that the fixed
piece 61 can sandwich or grip a portion of the sewing material A,
located above an insertion inlet of the tube 41 in conjunction with
the movable piece 53 of the sliding rod 52 as the sliding block 50
descends to the lowered position indicated by the two-dot-chain
line in FIG. 6.
[0049] Next, a description will be given about how the instant
embodiment of the sewing machine constructed in the aforementioned
manner performs an operation for sewing the sewing material A onto
the original fabric N that is a sewing object, an operation for
cutting the sewing material A after completion of the sewing
operation and an operation for pulling back the sewing material A
after completion of the cutting operation. First, a description
will be given about the operation for sewing the sewing material A
onto the original fabric N that is a sewing object.
[0050] The human operator pays out the sewing material A wound on
the bobbin 19 disposed above the machine head H and directs the
paid-out sewing material A to the needle drop position of the
sewing needle 14 by way of the guide member 29, back side of the
rod 33, guide collar 38, tube 41 and guide 18 as set forth above.
In this situation, lock switching is performed in the well-known
manner through cooperation between the sewing needle 14 and the
knot-shown rotary hook by not only controlling movement, in the
front-rear and left-right directions (see FIG. 1), of the fabric
frame 4, having an original fabric N set thereon, on the basis of
predetermined embroidering data but also driving the needle bar
vertically. During that time, the presser foot 16 is vertically
driven at predetermined timing relative to the vertical up-down
movement of the needle bar 14, as well known in the art.
[0051] The guide lever 17 is pivotally driven at predetermined
timing relative to the vertical up-down movement of the needle bar
14, so that the sewing material A, having been guided to the needle
drop position by the guide 18 fixed to the lower end of the guide
lever 17, is swung leftward and rightward per vertical
reciprocating movement of the needle bar 14 (i.e., per switch).
Thus, the sewing material A is sequentially sewn onto the original
fabric N through so-called zigzag sewing. During that time, the
rotary member 15 is rotationally controlled in accordance with a
moving direction of the fabric holder 4 based on predetermined
embroidering data so that the guide 18 is positioned ahead in a
relative advancing direction of the machine head H based on the
movement of the fabric N. In this manner, the sewing material A is
appropriately directed to the needle drop position of the sewing
needle 14.
[0052] As the sewing material A is sequentially sewn onto the
original fabric N in the aforementioned manner, the rod 33 is
pulled by the sewing material A to be moved toward the front, so
that the two pivot arms 34 and 35 are both pivoted in response to
the movement of the rod 33. Such pivoting movement of the pivot arm
34 is detected by a detector, on the basis of which the drive motor
24 is driven for a time set by the timer 36 to cause rotation of
the bobbin 19, so that the sewing material A is paid out from the
bobbin 19. Then, as the sewing material A is further sequentially
sewn onto the original fabric N, the two pivot arms 34 and 35 are
both pivoted again, in response to which the bobbin 19 is rotated
to further pay out the sewing material A. Namely, during the sewing
of the sewing material A onto the original fabric N, the bobbin 19
repeats starting and stopping its rotation as the sewing material A
is pulled in accordance with a progression of the sewing operation,
so that the sewing material A can be appropriately paid out to the
needle drop position of the sewing needle 14 in a smooth
manner.
[0053] Next, a description will be given about the operation for
cutting the sewing material A by means of the cutting device C in
response to completion of the sewing of the sewing material A onto
the original fabric N. Once the sewing of the sewing material A
onto the original fabric N is completed in the aforementioned
manner, the fabric frame 4 is moved in the front-rear and
left-right directions (see FIG. 1) in such a manner that a sewing
stop point of the sewing material A sewn onto the original fabric N
is moved from the needle drop position of the sewing needle 14 to a
predetermined position set near the cutting device C at a given
distance from the needle drop position. In response to such
movement of the sewing material A, the sewing material A (leading
end portion of the sewing material A) is pulled out (i.e., pulled
to extend out) from the guide 18 by a length corresponding to an
amount of the movement of the sewing material A from the needle
drop position to the predetermined position.
[0054] After the sewing stop point of the sewing material A is
positioned at the predetermined position near the cutting device C,
the cutting device C starts moving a cutting member from an
evacuation position to a cutting position. During such movement of
the cutting member from the evacuation position to the cutting
position, the sewing material A is caught by an engaging portion of
the cutting member. Then, as the cutting member with the sewing
material A caught by the engaging portion is moved from the
evacuation position toward the cutting position, a cutting blade of
the cutting device C is moved so that the sewing material A is cut
through cooperation between the cutting blade and a fixed blade.
Upon completion of the cutting of the sewing material A, the
cutting device C moves the cutting member from the cutting position
back to the evacuation position.
[0055] Next, a description will be given about the operation for
pulling up (i.e., pulling back) the sewing material A after
completion of the cutting operation. In the pulling device 44
constructed in the aforementioned manner, the sliding block 50 is
located in the raised position as indicated by the solid line in
FIG. 6 during the sewing operation. FIG. 7 shows such a state where
the sliding block 50 is located in the raised position. Namely, in
this state, the sliding rod 52 has slid to its leftmost position,
and the ball of the ball plunger 55 is retained in engagement with
the recessed portion formed in the front surface of the movable
piece 53.
[0056] After the sewing material A is cut by the cutting device C
upon completion of the sewing operation, first, the air cylinder 49
is activated or operated in a predetermined direction to start an
operation for lowering the sliding block 50 to the lowered position
indicated by the two-dot-chain line of FIG. 6, in order to pull
back the sewing material A having been paid out more than a length
necessary for the sewing material A to be reliably sewn onto the
fabric N at the beginning or initial stage of a next sewing
operation. Once the descending sliding block 50 reaches or arrives
at a position slightly before the above-mentioned lowered position,
the roller 56 of the sliding rod 52 abuts against the slanting
surface 58a of the lower cam 58. Then, as the sliding block 50
further descends from the position slightly before the
above-mentioned lowered position, the roller 56 is pushed by the
slanting surface 58a of the lower cam 58 so that the sliding rod 52
is slid rightwardly (see FIGS. 6 to 8).
[0057] As the sliding rod 52 is slid rightward to some extent in
the aforementioned manner, the engagement between the recessed
portion of the movable piece 53 and the ball of the ball plunger
55, so that the sliding rod 52 slides, by being urged by the
biasing force of the compression spring 54 as well, to a position
where a portion of the sewing material A located above the inlet of
the tube 41 can be sandwiched or gripped between the movable piece
53 and the fixed piece 61. FIG. 8 shows such a state. In the
aforementioned manner, the portion of the sewing material A located
above the inlet of the tube 41 can be sandwiched or gripped by the
movable piece 53 and the fixed piece 61. Note that, in the instant
embodiment, the position of the lower cam 58 in the elongated hole
47 is adjusted in such a manner that the sandwiching of the sewing
material A by the movable piece 53 and the fixed piece 61 takes
place substantially simultaneously with the arrival, at the lowered
position indicated by the two-dot-chain line of FIG. 6, of the
sliding block 50 take place at substantially the same time.
[0058] Next, the air cylinder 49 is operated in an opposite
direction from the aforementioned predetermined direction to start
an operation for raising the sliding block 50 from the lowered
position indicated by the two-dot-chain line of FIG. 6 back to the
predetermined raised position indicated by the solid line of FIG.
6. At that time, the sliding block 50 starts ascending with the
sewing material A kept sandwiched between the movable piece 53 and
the fixed piece 61 by the biasing force of the compression string
54. In this manner, the sewing material A kept sandwiched between
the movable piece 53 and the fixed piece 61 is pulled upward
together with the sliding block 50. Then, once the ascending
sliding block 50 arrives at a position slightly before the raised
position, the roller 56 of the sliding rod 56 abuts against the
slanting surface 57a of the upper cam 57. Then, as the sliding
block 50 further ascends from the position slightly before the
above-mentioned raised position, the roller 56 is pushed by the
slanting surface 57a of the upper cam 57 so that the sliding rod 52
is slid leftwardly (see FIGS. 6 to 8).
[0059] As the sliding rod 52 is slid leftward to some extent in the
aforementioned manner, the sewing material A is released from the
sandwiching or gripping between the movable piece 53 and the fixed
piece 61, upon which the pulling-up of the sewing material A is
terminated. Then, as the sliding block 50 further ascends, the
sliding rod 52 further slides leftward, so that, by the time the
sliding block 50 reaches the raised position, the recessed portion
of the movable piece 53 has returned back to the position where it
engages with the ball of the ball plunger 55.
[0060] As noted above, the pulling-up of the sewing material A is
carried out in response to the air cylinder 49 being operated to
cause one vertical reciprocating movement of the sliding block 50.
Namely, the sewing material A is pulled upward in response to the
sliding block 50 being first moved to the lowered position and then
moved back to the raised position. In this way, the length of the
leading end portion of the sewing material A, having been pulled to
extend out from the guide 18 more than necessary at the time of the
cutting operation by the cutting device C, can be reduced to a
length necessary for the sewing material A to be reliably sewn onto
the original fabric N at the initial phase of a next sewing
operation.
[0061] In the illustrated example of FIG. 6, the upper cam 57 is
fixed at a position that can maximize the pull-up (i.e., pull-back)
amount of the sewing material A. Note, however, the position at
which the upper cam 57 is fixed can be changed to any desired
position in the elongated hole 47a formed in the base 47. If the
upper cam 57 is fixed at a lower position than in the illustrated
example of FIG. 6, the timing at which the sewing material A is
released from the sandwiching between the movable piece 53 and the
fixed piece 61 is made earlier than in the illustrated example of
FIG. 6, and thus, the pull-up amount of the sewing material A can
be reduced. Namely, the pull-up amount of the sewing material A can
be changed in response to a change in the fixed position of the
upper cam 57 in the elongated hole 47a formed in the base 47.
[0062] According to the preferred embodiment of the sewing machine,
as set forth above, the length of the sewing material A, whose
leading end portion has been pulled to extend out more than
necessary at the time of the cutting operation by the cutting
device C, is pulled back by the pulling device (pulling member) 44
and thus can be reduced to the length necessary for the sewing
material A to be reliably sewn onto the original fabric at the
initial stage of the next sewing operation. In this way, the human
operator can minimize an unsewn portion, located ahead of a next
sewing start point, of the sewing material A; namely, the human
operator can minimize a wasted portion of the sewing material
A.
[0063] Further, the above-described pulling device 44 is
constructed to adjust as desired the pull-up amount of the sewing
material A by changing the position of the upper cam 57. Thus, the
human operator can readily adjust the length of the leading end
portion of the sewing material A, which is to be pulled to extend
out from the guide 18, to a desired length depending on the types
of the sewing material A and sewing object (original fabric N),
which should prove to be very convenient.
[0064] Although the preferred embodiment has been described above
with reference to the accompanying drawings, it should be
appreciated that various modifications are also possible. For
example, whereas the preferred embodiment has been described above
in relation to the pulling device 44 constructed to pull up the
sewing material A by ascending the sliding block 50, the present
invention is not so limited, and the pulling device 44 may be
constructed in any other manner as long as it can adjust, into a
shorter length, the length of the leading end portion of the sewing
material A which is to be pulled to extend out from the guide 18
for being reliably sewn onto the original fabric at the initial
phase of a next sewing operation.
[0065] This application is based on, and claims priority to, JP PA
2011-278225 filed on 20 Dec. 2011. The disclosure of the priority
application, in its entirety, including the drawings, claims, and
the specification thereof, is incorporated herein by reference.
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